The invention proceeds from a valve for carrying out a mass-transfer process, in which a gas flows through a liquid standing on an upper tray, when the gas supply is interrupted the liquid flows into a lock beneath the upper tray and, when the gas supply is restarted, the liquid flows out of the lock through a lower tray bordering the lock downward, wherein the valve comprises a closing element which comprises a piston rod, an upper valve disk and a lower valve disk and which is conducted in a sleeve, wherein the lower valve disk, in a first valve position, closes an opening at the lower end of the sleeve.
A valve for carrying out a mass-transfer process which is received in a separating tray comprising an upper tray and a lower tray, wherein, between the upper tray and the lower tray, a lock is formed, wherein the valve is designed in such a manner that, in one valve position, gas can flow through the separating tray and is passed through a liquid standing on the upper tray and, when the gas supply is interrupted, the valve, in a second position, ensures that the liquid can flow from the upper tray into the lock, is known for example from EP 2 033 698 A1, EP 2 027 901 A1 or RU 2 237 508 C1. The valves disclosed in these documents each comprise a closing element which comprises two valve disks which are connected to one another via a spacer. In a first position of the closing element, an outlet opening from the valve is closed by the lower valve disk, through which outlet opening the liquid can flow from the lower tray to the separating tray beneath. At the same time, the second valve disk is situated in a position which permits flow of the liquid from the upper tray into the lock. In a second valve position, the closing element is lifted in such a manner that gas can flow through the lower opening in the valve first into the lock and then can flow around the lower valve disk via openings in the valve housing through the lock in the direction of the upper tray, wherein the gas on the upper tray is passed through the liquid standing on the tray.
However, a disadvantage of the valve known from the prior art is that it can become blocked, in such a manner that the liquid does not flow out of the lock when gas supply is restarted or an excessive gas pressure is necessary in order to open the valve. This can lead to an impairment of the separation efficiency.
It is therefore an object of the present invention to provide valves for carrying out a mass-transfer process which function in a fail-safe manner in such a manner that the valves cannot twist and cannot become blocked as a result.